Idler Roller Chain Sprocket Bore Diameter 3/4 in Chain Number 80 Sprocket Material Steel Number of Teeth 12 Outside Diameter 4.33 in Bearing Type Ball For Number of Strands Single Length through Bore 39/64 in Lubrication Multi-Temperature Quality Bearing Grease Pitch Diameter 3.864 in Sprocket Width 0.61 in Standards ANSI Teeth Heat Treatment Hardened Teeth